The boat with its own speed of 20 km / h sailed for 4 hours along the river and 6 hours against the current.

The boat with its own speed of 20 km / h sailed for 4 hours along the river and 6 hours against the current. The entire route of the boat was 196 km. Find the speed of the river.

1. Take the speed of the river as x.

2. Speed of the boat along the river (20 + h) km / h.

Speed of the boat against the stream of the river (20 – x) km / h.

3. We compose and solve the equation:

4 (20 + x) + 6 (20 – x) = 196;

80 + 4x + 120 – 6x = 196;

200 – 2x = 196;

2x = 4;

x = 2 km / h.

Answer: the speed of the river is 2 km / h.